Drying apparatus



Jan. 21, 1941. vcz. l.. GEHNRICH DRYING APPARATUS 5 Sheets-6h72@` Filed March 13, 1939 TTORNEY INVENTOR Jan. 2l, 1941.

C. l. GEHNRICH DRYING APPmATUs Filed March 13., '1939 3 Sheets-Sheet 2 INVENTR Y BY ORNEY Jam 21, l941- c. L. GEHNRlcl-l 2,229,285

DRYING l APPARATUS Filed March 13, 1939 3 Sheets-Sheet 5 INVENTOR Patented Jan. 21, 1941 n y UNITED STATES PATENT OFFICE 2,229,285 DRYING APPARATUS' Charles L. Gehnrich, Elmhurst, N. Y.

Application March 13, 1939, Serial No. 261,471

3 Claims. (Cl. 34-24) This invention relates to apparatus for remov- In the drawings, ing volatile substances from moving Webs and Fig. 1 is a top plan view of a drying system emmore particularly to an apparatus for drying ink bodying the present invention. on webs of the type used in printing newspapers, Fig. 2 is a longitudinal vertical section through magazines or the like. the apparatus with parts variously broken away An object of the invention is to provide an apto show the arrangement of ducts. paratus for rapidly drying ink on traveling Webs Fig. 3 is a transverse vertical section taken so that the web can be immediately subjected to along the line 3 3 of Fig. 2 and i further printing or folding operations. Figs. 4, 5 and 6 are transverse horizontal sec- Another object is to provide for the rapid drytions taken along the lines 4 4, 5-5 and 6 6 10 ing of the inks used in color printing so that the respectively, of Fig. 2. p additional colors may be superimposed thereon Referring to the drawings more in detail, the without delay. invention is shown as applied to an apparatus' A further object is to provide for the rapid dryfOr the treatment of a web I0 which may coming of inks in high speed presses, particularly in prise the paper web received from a high speed high speed color presses so that the speed of printing press of the type used for printing newsprinting need not be reduced to aiford time for papers, magazines or the like. The web I0, Fig. the ink to dry Ibetween the various printings. 2, may be received from a printing roll by which In systems of this type it has been found that it has been printed on one side, for example, on passing the paper web in close relationship to a the under side as shown in Fig. 2. The impres- 20 heating unit does not produce the desired result sion may comprise one of the color components for the reason that the volatile constituents of of a multicolor printing job. The web I0, thus the ink driven from the paper cause an insulating printed, is passed around a roller II thence uplayer of vapor to form immediately adjacent wardly in a housing I2, to be described, and thereto, which eiectively blocks heat transfer around a second roller I3 on its way to a second 25 from the printing element to the paper, thereby printing roll by which an additional color comnecessitating either an increase in time of exponent is to b e applied thereto. posure to the heating element which reduces the The housing I2 includes a receiving section I5 speed of operations or the use ofextremely high which is shaped to receive the web IIJ from the temperatures with a resulting fire hazard. Furrst printing roll and a discharge section I6 30 thermore the re underwriters require the rethrough which the web is passed to the succeedmoval and' discharge to the atmosphere of a ing printing roll or to suitable folding or cutting specied minimum quantity of air, dependent apparatus as may be required. A hot air duct 20 upon the quantity of volatiles removed from the is mounted in the housing I2 atthe back of the Paper. V web, that is on the side opposite the printed sur- 35 It is accordingly the further object of the presface. This duct 20 is provided with a plurality ent invention to provide a drying system which of apertures 2| which are positioned to direct the eiectively removes the insulating layer of volaheated air received from a source to be described tiles from association with the web under treat-v on to the back of the web Ill and into the receiving 40 ment to thereby attain greater efliciency in drysection I 5 of the housing I2. The duct 20 is 40 ing while permitting the use of lower temperapreferably comparatively thin in section and extures. tends the full Width of the web. 1 Another object is to provide a system of the An additional hot air duct 25 is mounted in the above type which operates effectively and comhousing I2 and is provided with a plurality of plies in all respects with the underwriters specifihorizontally extending nozzles 26 which are 4 cations as to air discharge. adapted to direct the hot air from the duct 25 Although the novel features which are believed on to the printed surface of the web I0. These to be characteristic of this invention, are pointed nozzlesY 26 are horizontally spaced for the reaout more particularly in the claims appended son to Ibe set forth and extend over substantially hereto, the .nature ofthe invention will be betthe entire width of the web so that the hot air 50 ter understood by referring to the following dey from the duct 25 is directed across substantially scription taken in connection with the accomthe entire face thereof. panying drawings in which a specific embodivA lreturn duct 28 is also mounted within the ment thereof has .been set forth for purposes of housing I2 and is provided with a plurality of illustration. laterally extending nozzles-29 which are similar 55 to the nozzles 2B but are disposed alternately therewith, in a position to withdraw the air laden With volatile vapors from the surface of the web I0. As shown in Figs. 4 and 5 rthe ducts 25 and 28 are located at opposite sides of the housing I2 with the laterally extending nozzles 26 and 29 in. dovetailed relationship extending alternately therefrom.

The housing I2 is also provided with an exhaust duct 30 which is adapted to withdraw air through the spaces between the adjacent nozzles 26 and 29. A certain quantity of air laden with the volatile vapors is accordingly withdrawn from the space adjacent the web III, through the spaces between the adjacent nozzles above mentioned and is discharged to the atmosphere as will be described.

For supplying the heated air, a heater 40, Fig.`

1, of any suitable type such for example as a heater of the type shown in my Patent #2,077,043, may be used. This heater comprises in general an outer housing 4I to which cold air and return air is supplied and which is heated by heat supplied by burners 42 which may lbe supplied by any suitable type of fuel. The heated air from the heater 40 is passed through a duct 53 to a blower, such as a fan 44, driven by a belt I5 from a motOr 46. leading to the supply duct and also to a duct 48 leading 25 above mentioned to the hot air duct The return air from the duct 28 is taken through a duct 50 to the intake side of the heater 40 for recirculation. The exhaust air from the duct 30 is taken to a blower 5I operated by a suitable motor 52 whence it is discharged into the atmosphere. The quantity of air so discharged may be controlled by suitable regulation of the motor 52 or by a damper 53. The quantity of hot air supplied to the ducts 20 and 25 may be controlled by regulation of the motor 46. Suitable dampers may also be included in the various ducts to effect independent control of the operation thereof.

In the operation of this device, heated air is supplied to the web I through the apertures 2I in the hot air duct 20 and through the nozzles 26, associated with the hot air duct 25. This air may be heated to a perature, such for example as around 400 F. to 800 F., depending upon the type of work involved, and is supplied to a plurality of horizontally spaced portions of the web as the latter is fed upwardly pastvthe various nozzles. The hot air causes the volatile constituents of the ink to be driven off. The volatile laden air, however, is immediately withdrawn from contact with the web through the nozzles 29 and.

the duct 50 and also through the housing I2 and the duct 30 so that the building up of an insulating layer of volatile matter is prevented. A portion of the heated air thus removed is recirculated by means of the duct 50 just mentioned.A A prescribed portion, however, is removed and discharged through the atmosphere by means of the duct 30, this portion being determined in accordance with the underwriters requirements and in accordance with the desired operating conditions.

Inasmuch as the volatile layer is immediately removed from contact with the web, the drying operation is facilitated and the use of high temperatures is avoided. The temperature of the heated air is preferablymaintained sufllciently low `so that theweb will not bum should it re-A The fan 44 discharges to a duct 41 comparatively low temmain stationary in the housing I2 for an appreciable period of time, due for example to stopping the presses. Suitable control means may also be provided to shut oif the fuel supply to the burner when the press stops. This immediately reduces the gas temperature as the fans 44 and 5I continue to operate.

It is to be noted that the ducts 25 and 28 are tapered in section toward the bottom of the housing. This tapered section is designed to maintain an equalized air pressure in the various nozzles 26 and 29 and to maintain a uniform air flow throughout the apparatus so that the web may be subjected to uniform and controlled conditions of treatment. A suflicient suction is maintained on the housing I2 lby means of the blower I so that 4a positive pressure differential is maintained between the outside atmo'sphere and the interior of the housing, thus preventing escape of the vapors. The pressure differential is preferably maintained as low as possible so as to minimize the quantity of air leaking into the interior of the housing I2 through the various openings thereof.

It has 'been found that in using this apparatus for drying `colored ink on Webs received from'higl 'speed presses, the drying operation takes place during the time required for the web to pass through thehousing I2. This results in a greatly increased speed of printing, particularly when a plurality of colors are to be superimposed and by reason of the efficient drying between printing oper-ations, results in an improved quality of printing. Furthermore the uniform treatment at a comparatively low temperature, prevents surface hardening and cracking of the inln Although a specific embodiment of the invention has been set forth above, it is to be understood that the invention is capable of various uses as will be readily apparent to a person skilled in the art. Certain specific terms have been used herein for convenience of description and not as a limitation on the scope of the invention. The invention is only to be limited in accordance with the following claims.

What I claim is:

1. The method of removing volatile constituents from a traveling web passing through a housing, which comprises passing a gas through a heating zone to heat the same to an elevated temperature, supplying said heated gas to said web at a. plurality of supply zones spaced along its path of travel in said housing, removing a portion of the vapor laden gases from a plurality of exhaust zones intermediate said supply zones, recirculating said gases to said heating zone, removing the remainder of the vapor laden gases in a. direction substantially normal to the web from a plurality of discharge zones located between said supply and exhaust zones and discharging the gases from said last zones to a point external to said housing.

2. An apparatus for removing a volatile constituent from a. traveling web comprising a housing through which said web is passed, a hot air duct and an exhaust duct, a lset of nozzles in said housing, each nozzle having a. mouth extending transversely across said web close to the printed side thereof, said nozzles being spaced along the path of travel of said web, alternate nozzles being connected respectively to said hot air and exhaust ducts to respectively discharge hot air onto said web and to remove vapor .laden air therefrom, an airheater connected to 2,229,285 .said exhaust duct, a blower connected between said heater and said hot air duct constructed and arranged to recirculate heated air through said ducts and nozzles, adjacent nozzles being spaced apart to provide a transverse passage therebetween, a discharge duct communicating with said passages to remove vapors through said y passages in a direction normal to said web, and

a suction blower connected to said discharge duct to induce a owof vapors'therethrough, said suction means being connected to discharge said gases to an external point.

3. An apparatus for removing a volatile conlstituent from a traveling web comprising a housing through which said web is passed, a hot air duct and an exhaust duct associated with said housing, a set of nozzles, each nozzle having a mouth extending transversely across the web close to the printed side thereof, said nozvzles beingjspaced along the path of travel of said web, alternate nozzles being connected re spectively to said hot air duct and said exhaust duct to respectively discharge hot air onto said web and to remove vapor laden air therefrom, adjacent nozzles being spaced apart to provide passages in said housing therebetween and exhaust meanscommunicating with said passages to Withdraw part of the vapor laden air through said passages in a direction substantially normal to the web and to exhaust the same to the atmosphere.

CHARLES L. GEHNRICH. 

